From: Alan T. DeKok <aland@freeradius.org>
Date: Wed, 6 Mar 2024 14:18:47 +0000 (-0500)
Subject: add first / last API
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=df8ccf9cc344fc66010f61eb60f8606857e0edb0;p=thirdparty%2Ffreeradius-server.git

add first / last API
---

diff --git a/src/lib/util/rb.c b/src/lib/util/rb.c
index a7377cff818..a94d2f630d9 100644
--- a/src/lib/util/rb.c
+++ b/src/lib/util/rb.c
@@ -777,6 +777,36 @@ uint32_t fr_rb_num_elements(fr_rb_tree_t *tree)
 	return tree->num_elements;
 }
 
+void *fr_rb_first(fr_rb_tree_t *tree)
+{
+	fr_rb_node_t *x = tree->root;
+
+	if (x == NIL) return NULL;
+
+	/*
+	 *	First node is the leftmost
+	 */
+	while (x->left != NIL) x = x->left;
+
+	return x->data;
+}
+
+
+void *fr_rb_last(fr_rb_tree_t *tree)
+{
+	fr_rb_node_t *x = tree->root;
+
+	if (x == NIL) return NULL;
+
+	/*
+	 *	Last node is the rightmost
+	 */
+	while (x->right != NIL) x = x->right;
+
+	return x->data;
+}
+
+
 /** Initialise an in-order iterator
  *
  * @param[out] iter	to initialise.
diff --git a/src/lib/util/rb.h b/src/lib/util/rb.h
index 28f874dffcf..0fe56ccec7a 100644
--- a/src/lib/util/rb.h
+++ b/src/lib/util/rb.h
@@ -295,6 +295,10 @@ bool 		fr_rb_delete_by_inline_node(fr_rb_tree_t *tree, fr_rb_node_t *node) CC_HI
 
 uint32_t	fr_rb_num_elements(fr_rb_tree_t *tree) CC_HINT(nonnull);
 
+void		*fr_rb_first(fr_rb_tree_t *tree) CC_HINT(nonnull);
+
+void		*fr_rb_last(fr_rb_tree_t *tree) CC_HINT(nonnull);
+
 /** Check to see if an item is in a tree by examining its inline #fr_rb_node_t
  *
  * This works because we use NIL sentinels to represent the absence of a child